Key-lock for autopianos.



AW.1L .B,MIER. KEY Loox ron AUToPIANos. APPLICATION FILED IB.31,1909.

981,158. PanendJmw, 1911.

-z SHEETS-SHEET z.

idw(- UNITED STATES* PATENT OFFICE.

WILLIAM F. BAYER, OF BUFFALO, NEW YORK, ASSIGNOR TO THE CHASE & BAKER COMPANY, QF BUFFALO, NEW YORK, A CORPORATION OF NEW YORK.

KEY-LOCK FOR AUTOPIANOS.

Specification of Letters Patent.

Patented Jan. 10, 1911.

Application filed March 31, 1909. Serial No. 486,894.

lb all whom tt may cof/wem:

Be it known that I, WILLIAM F. BAYER, a citizen of the United States, residing at Buffalo, in the county of Erie and State of New York, have invented a new and useful Improvement in Key-Locks for Autopianos, of which the following is a specification.

This invention relates to the key-locks employed in combined automatic and manuallyoperated pianos and similar musical instruments for preventing vibration of the keys when the instrument is operated automatically.

It is the object of my invention to provide a simple, convenient and inexpensive locking device of this character.

In the accompanying drawings consisting of 2 sheets: Figure 1 is a fragmentary front elevation of an auto-piano provided with the in'iliirovement, the front panel of the case, the strings and the piano-action being omitted. Fig. 2 is a horizontal section on line 2 2, Fig. 1. Figs. 3 and 4L are transverse sections on the correspondingly-numbered lines in Fig. 1.

Similar let-ters of reference indicate corresponding parts throughout the several views.

A. indicates the piano-keys fulcrumed on the usual balance-rail a., and Z) one of the abstracts of the piano-action (not shown) which are manually operated by the keys. In the construction shown in the drawings by way of example, the lower portion of the abstract is guided by a vertically-swinging link c pivoted at its rear end to a hanger cl which is secured to a fixed horizontal supporting rail I). Each of these links is piv.

oted to the corresponding abstract at c1 and projects forwardly beyond the same to form an extension c2. Under this extension engages the rear arm of a vertically-swinging lever E which is actuated by the corresponding motor pneumatic F of the pneumatic action of the instrument. This pneumatic action and the wind chest G thereof may be of any suitable construction; they form no part of my invention and therefore require no detailed description. In the construction shown, the front arm of the lever E is connected by a rod f with the usual arm f1 of the upper movable board of the corresponding motor pneumatic, so that when the latter is collapsed it operates t-he companion abstract b in a common manner.

H indicates a vertically-movable key-locking rail arranged transversely underneath the front portions of the various piano-keys and adapted to be raised into contact with their under-sides, as shown in Fig. 1, for locking them against vibration when the instrument is operated automatically, or to be lowered to the position shown in Fig. 3, for unlocking the keys and permitting them to be depressed in the customary manner in playing the instrument manually. In the preferred construction shown in the drawings, this locking rail extends throughout the series of keys and is provided at suitable intervals with depending guide pins or plungers z' suitably secured to its underside and sliding in openings in the key table J.

Arranged on the underside of the key table and cooperating with the guide-pins i are upright cams or eccentrics 7c, one for each pin. These eccentrics bear with their peripheries against the lower ends of the pins and are secured to a rock shaft K arranged lengthwise underneath the key table and supported in suitable bearings Z, secured thereto. In the construction shown,the keytable is provided in its underside with recesses which receive the eccentrics, one of such recesses being shown at cl, in Fig. ll. The rock shaft K has a hand lever m or other suitable means for turning it, said lever being conveniently located near the right "land end of the shaft, in the construction shown in the drawings.

In the lowered inoperative position of the key locking rail H, it rests upon the key table and the narrow portions of the eccentrics 7c face or bear against the lower ends of the guide pins z', as shown by dotted lines in Fig. 3, the hand lever preferably occupying an approximately horizontal position, as shown.

lhen it is desired to lock the keys, the hand lever is swung downwardly and rearwardly to the'position shown in Fig. 4t, thereby rotating the eccentrics 7c in the proper direction to raise the pins e' and elevate the rail H against the underside of the keys. The throw of the eccentrics is preferably such that they cause the locking rail, when elevated, to lift the keys slightly ot'tl the balance rail, the rear ends of the keys resting in that case upon the key table or the usual rail n thereof. By this construction of the locking device, the keys are removed from their central or main fulerum for the timebeing, so that any impact received by their customary capstan screws 0 by the movements of the abstracte Z) does not produce a rocking action or vibration of the keys. The eccentric-shaft is preferably arranged vin vertical alinement with the guide pins z', as shown. rlhe movement of the eeeentries beyond the position shown in Fig. l is limited by a stop-block j; on the front of the ease which is engaged by the hand lever, or by any other Suitable meana. Upon turning the hand lever to the position shown in Fig. 3, the locking rail descends to its unlocking pofsition by its own weight and that of the keys, which latter resume their normal position upon the balance rail.

The simplicity of my improvement renders its Cost comparatively Small, while its construction and arrangement are such that it is readily applicable to existing as well as new instrumente.

l claim as my invention:

l. The combination of the key-table, the

piano-keys, a vertieally-movable locking rail extending across the undersides of the keys, a guide-member carried by the locking rail and extending into the key-table, and a rock shaft arranged underneath the key-table and having an eccentric which engages said member for elevating the locking rail.

2. The combination of the key-table, the piano keys, a vertically-movable locking rail extending acroSs` the undereides` of the keys, guide-pins Secured to the locking rail and extending downfardly into the keytable, a rock shaft arranged lengthwise underneath the key-table and having an oper ating device, and eceentrics mounted on said Shaft and engaging the lower ends of Said guide-pins.

Vitness my hand thif: 19th day of March, 1909.

VILLIAM F. BAYER.

VitneSSes C. F. GnYEn, E. M. GRAHAM. 

